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  1. // Calculate Nth Fibbionacci number in O(log N)
  2. object Milk{
  3. 	// Matrix multiplication
  4. 	def matmul(mat1 : Array[ Array [Int] ], mat2 : Array[ Array [Int] ]): Array[ Array [Int] ] = {
  5. 		val n = mat1.size;
  6. 		var res = new Array[ Array [Int]](n, n);
  7. 		for(i <- 0 until n){
  8. 			for(j <- 0 until n){
  9. 				res(i)(j) = 0;
  10. 				for(k <- 0 until n){
  11. 					res(i)(j) += mat1(i)(k) * mat2(k)(j);
  12. 				}
  13. 			}
  14. 		}
  15. 		return res;
  16. 	}
  17. 	// Matrix powering
  18. 	def matpow(mat : Array[ Array [Int] ], pow : Int): Array[ Array [Int] ] = {
  19. 		val n = mat.size;
  20. 		var res = new Array[ Array [Int]](n, n);
  21. 		for(i <- 0 until n){
  22. 			for(j <- 0 until n){
  23. 				if(i == j) res(i)(j) = 1;
  24. 				else res(i)(j) = 0;
  25. 			}
  26. 		}
  27. 		while(pow > 0){
  28. 			if(pow % 2){
  29. 				res = matmul(res, mat);
  30. 			}
  31. 			mat = matmul(mat, mat);
  32. 		}
  33. 		return res;
  34. 	}
  35. 	// Calculate sum of a
  36. 	def fibb(n : Int): Int = {
  37. 		var mat = new Array[ Array [Int]](2, 2);
  38. 		mat(0)(0) = 1; mat(0)(1) = 1; mat(1)(0) = 1; mat(1)(1) = 0;
  39. 		mat = matpow(mat, n);
  40. 		return mat(1)(0);
  41. 	}
  42. 	// Main function
  43. 	def main(args : Array[ String ]) = {
  44. 		val n = args.size;
  45. 		for( i <- 0 until n) a(i) = println(fibb(args(i).toInt));
  46. 	}
  47. }
  48.  
Compilation error #stdin compilation error #stdout 0s 0KB
comments (?)
stdin
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Standard input is empty
compilation info 
Main.scala:28: error: type mismatch;
 found   : Int
 required: Boolean
			if(pow % 2){
                               ^
Main.scala:31: error: reassignment to val
			mat = matmul(mat, mat);
                            ^
Main.scala:45: error: not found: value a
		for( i <- 0 until n) a(i) = println(fibb(args(i).toInt));
                                     ^
three errors found
stdout
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Standard output is empty
https://ideone.com/wZysH
language:
Scala (scala 2.12.8)
created:
14 years ago
visibility:
public

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